Sources tell Expreview that AMD is working on a new graphics processor (apart from the mysterious RV790), as an immediate reaction to the 55nm high-end GPUs NVIDIA is set to release. NVIDIA on its part is working on GeForce GTX 260 (55nm), GeForce GTX 285 (successor to GeForce GTX 280) and the dual-GPU monstrosity, GeForce GTX 295. To rival this, according to the source, AMD is working on the RV775 and derivatives based on its yields' performance.

These GPUs are slated for January thru March 2009. It has some very interesting specifications. To begin with, 840 stream processors. While stream processors on a current generation RV770 cannot be added/subtracted in quantities of 40 stream processors, perhaps, the increment of 40 SPs is derived from an extra ALU cluster the RV770 comes with by default (which helps in die harvesting, where the spare ALU cluster makes up for any damaged cluster, thereby improving yields). This would require near-perfect GPUs in the making (if re-engineering of the RV770 on a large scale is to be avoided). Another interesting point is regarding the smaller die. At this point we are clueless as to how that is possible without re-engineering the RV770 at a large scale. Treat yourselves to the specifications meanwhile:

The only explanation that i can see for a smaller die with more shader clusters is, that the yields must be so high and perfect after producing so many cores on 55nm process, that ATI is confident now to put lesser or maybe no spare shader clusters in the die for die harvesting

While the RV770 comes in 800 / 640 (and lol 560) SP configurations, physically the die could be having more than 800 SPs (> 10 ALU clusters). These are spare components that AMD activates to replace damaged/dysfunctional ALU clusters (and increase yields). About the "smaller die" part, I'm just as clueless as you are.

That number is strange. AFAIK RV770 comes with one extra Shader Processor per cluster, that is 17 instead of the 16. 10 clusters x 16 SP x 5 ALU = 800 AND 17 x 10 x 5 = 850, not 840. Maybe just a typo when the mysterious source sent the info.

Anyway IMO this is false or just some kind of viral marketing to the RV790 or is the RV790 in any case. BUt BOTH won't be released IMO.

ohh i see the most impressive thing amd add more 8 texture unit , that's nice , and also i see amd back to old names pro and xt , and see the hell rv775xt have 900mhz core speed , dumm , and what about overclock did i expect to see first gpu run at 1ghz

There are some issues in the table, which may be causing confusion for us:

RV770 has 956 million transistors according to some sites, and 965 million according to others. Somewhere there is a typo. Let's assume 956 is correct since this is the most popular, then

How would ATI REDUCE the number of transistors whilst INCREASING the number of shaders. What is being changed here? Unless there is another typo and they are increasing the transistor count and going from 55nm to 50 nm. OR they are reducing voltage and increasing the density WITHIN 55nm scale to get the same or more transistors in a smaller space. BUT that is a major tape-out redesign issue.

The table and the technology and the statement no major redesign is mutually inconsistent.

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What I dont like is that for ATI/AMD shaders are NOT the bottleneck, but TMU and ROPs are: see http://forums.techpowerup.com/showthread.php?p=1062008.
Therefore meh! They are adding something that doesnt add performance value. They are "fixing" the wrong end of the stick.

What I dont like is that for ATI/AMD shaders are NOT the bottleneck, but TMU and ROPs are: see http://forums.techpowerup.com/showthread.php?p=1062008.
Therefore meh! They are adding something that doesnt add performance value. They are "fixing" the wrong end of the stick.

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I think the key "improvement" would be the 900 MHz clock + 20% more ROPs (not too shabby, I'd say). Besides, 40 more shaders seems unlikely (1 SIMD is 16x5=80 SPUs). They could also ditch the sideport, which is not used at all and save some space on that. All in all, I don't think the info is reliable.

The table and the technology and the statement no major redesign is mutually inconsistent.

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Agreed. I firstly didn't notice there were 48 texture units. That makes my typo theory impossible. That would mean either they did a mayor redesign to the SP/TMU clusters or that they added 2 clusters. In any case numbers don't fit or are inconsistent to the statement no major redesign.

Plays battlefield 3 well enough that i was ranked 1st globally in vehicles for november and december

i would lean more towards them releasing sub par numbers under what is really going to be released
remember last time they where saying 400 sp's or 600 or whatever, and it turned out to be 800, does anyone else make this connection ?

i would lean more towards them releasing sub par numbers under what is really going to be released
remember last time they where saying 400 sp's or 600 or whatever, and it turned out to be 800, does anyone else make this connection ?

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Yeah but back then they were posting numbers that made sense. This ones scream "we are FAKE" so what's the point??

AMD/ATi are working on something ofcourse, now if its this new 775 then good for them, but i dont think so. With less then 2 months to go, things would have been a little more clearer, like the 295GTX - already pictures of the completed card are circulating.

Cool, that means nothing really new from ATi until late 2009, hopefully nVidia will follow the trend(after G200b of course). Maybe it is just me, but I miss the days were we would see some time between major releases. I would like to actually keep the same graphics card in my machine for at least a year. I haven't done that since my 7900GT's, and I was hoping the upgrade to G200b would hold me over for a year.